[comment {-*- tcl -*- doctools manpage}]
[include parts/definitions.inc]
[vset VERSION 1.3.1]
[manpage_begin [vset LABEL_VALIDATE] [vset MAN_SECTION] [vset VERSION]]
[include parts/module.inc]
[require cmdr::validate]
[titledesc [vset TITLE_VALIDATE]]
[description]
[include parts/welcome.inc]
[para] Validation types are [vset PTITLE]'s answer to the necessity of
moving between the string and internal representations of
[package cmdr::parameter] instances.
[para] This internal package implements the twelve standard validation
types shown below. The [cmd validate] command of the parameter
declaration DSL can use these by name. Non-standard types have to
provide a proper command prefix instead.
[para] Readers interested in writing their own custom validation types
should read [term [vset TITLE_DEV_VT]].
[section {Standard Types}]
[include parts/vtypes_std.inc]
[section {Standard Selection Rules}]
[para] Because of the aformentioned necessity all parameters must have
a validation type assigned to them, and the framework will choose
which, if the user did not. This choice is made per the six rules
below and always returns one of the builtins described here.
[list_begin enumerated]
[enum] Use [const identity] if a [cmd generate] callback is specified.
[enum] Use [const boolean] if no [cmd default] is specified and the parameter is an [term option].
[enum] Use [const identity] if no [cmd default] is specified and the parameter is an [term input].
[enum] Use [const boolean] if the specified [cmd default] value is a Tcl boolean.
[enum] Use [const integer] if the specified [cmd default] value is a Tcl integer.
[enum] Use [const identity] as fallback of last resort.
[list_end]
[include parts/feedback.inc]
[manpage_end]
